Lip-type seal

ABSTRACT

The lip-type seal of the present invention is a lip-type seal with which the outer periphery of a rotational shaft (S) supported by a predetermined housing (H) is sealed. The lip-type seal is made up of a first annular reinforcing member ( 11 ) and a first sealing member ( 12 ). The first reinforcing member ( 11 ) includes a wall surface part ( 11   a ) defining a hole through which the rotational shaft (S) is passed and a cylindrical part ( 11   b ) bent from the outer edge of the wall surface part ( 11   a ). The first sealing member ( 12 ) includes an annular base ( 12   a ) that is joined to the housing (H), a first lip part ( 12   b ) that extends almost conical from the base ( 12   a ) inwardly in the radial direction and that comes into contact with the rotational shaft (S), and an annular concave part ( 11   c ) formed on the base ( 12   a ) so as to detachably fit the cylindrical part ( 11   b ). Accordingly, a desired sealing capability can be secured, and the components can be easily assembled, disassembled, and recycled.

TECHNICAL FIELD

The present invention relates generally to a lip-type seal with whichthe space between a housing and a rotational shaft, such as that of acompressor used in an air conditioning system of, for example, avehicle, is sealed, and, more particularly to a lip-type seal that canbe recycled.

BACKGROUND ART

In recent years, the technology for recycling a used lip-type seal hasbeen developed as part of the environmental antipollution measures. Asshown in FIG. 1, a conventional lip-type seal formed in consideration ofrecycling is known (see Japanese Published Unexamined Patent PublicationNo. 2002-364759, for example). This conventional lip-type seal is madeup of a metallic core ring 1, a first rubber-made sealing member 2 thatcontains the core ring 1 and that is shaped almost conical, a secondresinous sealing member 3 that adjoins the first sealing member 2 andthat is shaped almost conical, and a metallic backup ring 4 that adjoinsthe second sealing member 3.

In this lip-type seal, the first sealing member 2 includes an annularbase 2 a joined to a housing H, for example, of a compressor, a lip part2 b that defines an inner edge in contact with a rotational shaft Srotatably supported by the housing H, an annular containing part 2 c andan incision 2 d to which the core ring 1 is fitted in the base 2 a. Thesecond sealing member 3 includes a substantially flat outer edge part 3a, and a lip part 3 b that defines an inner edge in contact with therotational shaft S. The backup ring 4 includes a cylindrical part 4 athat is fitted to the inside of the base 2 a and a wall surface part 4 bthat defines a circular hole through which the rotational shaft S ispassed.

In order to assemble these components, the incision 2 d of the firstsealing member 2 is greatly widened, and the core ring 1 is insertedinto the containing part 2 c. Thereafter, the second sealing member 3 isinserted into the inside of the first sealing member 2, and the backupring 4 is incorporated by fitting the cylindrical part 4 a to the insideof the base 2 a in such a way as to sandwich the second sealing member 3between the first sealing member 2 and the backup ring 4.

However, in the assemblage into the lip-type seal, there is a need togreatly widen the incision 2 d while the base 2 a is being deformed andmaintain that state when the core ring 1 is inserted into the containingpart 2 c, and hence workability is remarkably inferior in assembling. Onthe other hand, a difficulty lies in detaching the core ring 1 when thecore ring 1 is attempted to be detached therefrom after the lip-typeseal is used for a long time, because the core ring 1 is completelyburied in the containing part 2 c so that there is no part to begripped, and the core ring 1 is in a state of having been firmlyembedded as a result of longtime use.

Additionally, in the assembled state of the lip-type seal, the secondsealing member 3 is sandwiched between the first sealing member 2 andthe backup ring 4. However, since the first sealing member 2 is made ofrubber, there is a fear that the second sealing member 3 cannot bereliably sandwiched therebetween because of its elastic deformation ortime-dependent change.

The present invention has been made in consideration of thesecircumstances of the prior art, and it is an object of the presentinvention to provide a lip-type seal in which components can be easilyassembled while securing the sealing function inherent therein, in whichthe components can be easily disassembled and sorted out, and in whichthe components can be recycled.

DISCLOSURE OF INVENTION

The lip-type seal of the present invention that achieves the object is alip-type seal with which the outer periphery of a rotational shaftsupported by a predetermined housing is sealed. The lip-type seal ismade up of a first reinforcing member formed annularly and a firstsealing member. The first reinforcing member includes a wall surfacepart defining a hole through which the rotational shaft is passed and acylindrical part bent from the outer edge of the wall surface part. Thefirst sealing member includes an annular base that is joined to thehousing, a first lip part that extends almost conical from the baseinwardly in the radial direction and that comes into contact with therotational shaft, and an annular concave part formed on the base so asto detachably fit the cylindrical part of the first reinforcing member.

According to this constitution, the cylindrical part of the firstreinforcing member is merely fitted into the annular concave part formedon the base of the first sealing member (without a caulking process oran adhesive), whereby the cylindrical part and the annular concave partare completely attached to each other. On the other hand, thecylindrical part and the annular concave part can be separated andsorted from each other merely by pulling out the cylindrical part fromthe annular concave part. Since the wall surface part of the firstreinforcing member has the wall surface part that is integrally formedwith the cylindrical part and that is in an exposed state although thecylindrical part is fitted into the concave part of the first sealingmember and is in a buried state, the first reinforcing member can beeasily pulled out from the first sealing member by gripping the wallsurface part (while putting a finger into the hole or using a tool).Thus, the components can be easily attached and detached.

In the above constitution, the first reinforcing member may have aninner cylindrical part that supports the base in a sandwiched mannerfrom the inside in cooperation with the cylindrical part, and the wallsurface part of the first reinforcing member may extend from the innercylindrical part.

According to this constitution, when the cylindrical part of the firstreinforcing member is fitted into the concave part of the first sealingmember, the inner cylindrical part of the first reinforcing membersupports the base (i.e., part defined by the concave part and by theinner circumferential surface) in the radial direction in a sandwichedmanner in cooperation with the cylindrical part located outside, andhence the cylindrical part and the concave part can be firmly attachedto each other more reliably.

In the above constitution, the wall surface part of the firstreinforcing member may be contiguous to the root area of the first lippart in the axial direction of the rotational shaft.

According to this constitution, since the wall surface part of the firstreinforcing member serves to support the root area of the first lippart, the first lip part can be prevented from being deformed beyond apredetermined range. Additionally, since the wall surface part is merelydisposed so as to be adjacent to the root area of the first lip part,these components can be easily detached from each other without trouble.

In the above constitution, the lip-type seal may further include asecond sealing member sandwiched between the first reinforcing memberand the first sealing member and a second reinforcing member formedannularly and fitted to the first sealing member on the side oppositethe first reinforcing member. The second sealing member may include ato-be-sandwiched part sandwiched between the wall surface part of thefirst reinforcing member and the root area of the first lip part and asecond lip part that extends almost conical from the to-be-sandwichedpart inwardly in the radial direction and that can come into contactwith the rotational shaft. The second reinforcing member may include anannular wall surface part that is brought into contact with the base inthe axial direction of the rotational shaft and a cylindrical part thatis bent from the inner edge of the annular wall surface and that isfitted to the inside of the base.

According to this constitution, the first reinforcing member, the firstsealing member, the second sealing member, and the second reinforcingmember can be completely assembled merely by fitting the cylindricalpart of the first reinforcing member into the concave part of the firstsealing member while supporting the to-be-sandwiched part of the secondsealing member in a sandwiched manner and by fitting the cylindricalpart of the second reinforcing member into the inside of the base. Onthe other hand, these components can be disassembled and sorted fromeach other merely by pulling out the cylindrical part of the firstreinforcing member from the concave part and by pulling out thecylindrical part of the second reinforcing member from the inside of thebase. Since the base of the first sealing member is sandwiched betweenthe cylindrical part of the first reinforcing member and the cylindricalpart of the second reinforcing member, the components can be assembledmore reliably.

In the above constitution, the first sealing member may be made ofrubber, and the second sealing member may be made of resin.

According to this constitution, since the first sealing member and thesecond sealing member can be easily separated as mentioned above, thesecomponents can be easily sorted from each other for recycling even ifcomponents differing in kind are used.

In the above constitution, the cylindrical part of the secondreinforcing member may have a contact part that comes in contact withthe root area of the first lip part in the axial direction of therotational shaft.

According to this constitution, as a result of attaching the secondreinforcing member, the contact part located at the end of thecylindrical part reliably supports the second sealing member (theto-be-sandwiched part) in a sandwiched manner in cooperation with thewall surface part of the first reinforcing member while restricting thedeformation of the root area of the first lip part. Therefore, thesecond sealing member is attached more reliably.

In the above constitution, the wall surface part of the firstreinforcing member may be provided with a rotation stopper thatrestricts the rotation of the second sealing member.

According to this constitution, the rotation stopper can prevent thesecond sealing member from being rotated although the second sealingmember is merely sandwiched between the first reinforcing member and thefirst sealing member.

In the above constitution, the second reinforcing member may have arestriction part that is bent from the cylindrical part inwardly so asto be cylindrical and that restricts the deformation of the first lippart outwardly in the radial direction of the first lip part within apredetermined range.

According to this constitution, since the cylindrical restriction partis provided in such a way as to surround the first lip part outside inthe radial direction of the first lip part, the first lip part can beprevented from being deformed outwardly beyond the allowable limits, anda desired sealing capability can be secured.

In the above constitution, an annular spring that exerts an urging forceinwardly in the radial direction in the outer peripheral area of thefirst lip part may be detachably attached to the first sealing member.

According to this constitution, since the annular spring is provided inthe outer peripheral area of the first lip part, the first lip part canbe prevented from being deformed outwardly beyond the allowable limits,and a desired sealing capability can be secured. Additionally, since thespring is detachably attached, the components can be easily assembledand disassembled.

In the above constitution, a third reinforcing member that is formedannularly and that restricts the deformation caused inwardly in theradial direction of the first lip part within a predetermined range maybe sandwiched between the first sealing member and the second sealingmember.

According to this constitution, the third reinforcing member can preventthe first lip part from being deformed inwardly in the radial directionbeyond the allowable limits, and a desired sealing capability can besecured. Additionally, since the third reinforcing member is merelysandwiched between the first sealing member and the second sealingmember, the third reinforcing member can be easily attached anddetached.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a partially sectional view showing a conventional lip-typeseal.

FIG. 2 is a partially sectional view showing a schematic structure of acompressor to which a lip-type seal according to the present inventionis applied.

FIG. 3 is an exploded perspective view showing an embodiment of thelip-type seal according to the present invention.

FIG. 4 is a partially sectional view of the lip-type seal of FIG. 3.

FIG. 5 is an exploded perspective view showing another embodiment of thelip-type seal according to the present invention.

FIG. 6 is a partially sectional view of the lip-type seal of FIG. 5.

FIG. 7 is a partially sectional view showing another method forattaching the lip-type seal of FIG. 5.

FIG. 8 is an exploded perspective view showing still another embodimentof the lip-type seal according to the present invention.

FIG. 9 is a partially sectional view of the lip-type seal of FIG. 8.

FIG. 10 is an exploded perspective view showing still another embodimentof the lip-type seal according to the present invention.

FIG. 11 is a partially sectional view of the lip-type seal of FIG. 10.

FIG. 12 is an exploded perspective view showing still another embodimentof the lip-type seal according to the present invention.

FIG. 13 is a partially sectional view of the lip-type seal of FIG. 12.

BEST MODE FOR CARRYING OUT THE INVENTION

The most preferred embodiments of the present invention will behereinafter described with reference to the attached drawings. Herein, adescription is given of a case in which a lip-type seal according to thepresent invention is used in a compressor C that serves as a part of anair conditioning system, for example, of a vehicle.

As shown in FIG. 2, a compressor C includes a housing H that defines theoutline, a rotational shaft S that is contained in the housing H andthat transmits a rotational driving force to a compression mechanismfrom the outside, and a lip-type seal 10 that blocks the air A and aninternal space B from each other by sealing a space between the outerperipheral surface of the rotational shaft S and the housing Htherewith.

As shown in FIG. 3 and FIG. 4, the lip-type seal 10 is made up of afirst reinforcing member 11 formed annularly and a first sealing member12 formed annularly.

As shown in FIG. 3 and FIG. 4, the first reinforcing member 11, which isformed by subjecting a metallic plate, such as a cold-rolled steel stripor a stainless steel plate, to press working, has a wall surface part 11a that defines a circular hole 11 a′ through which the rotational shaftS is passed, a cylindrical part 11 b that is bent from the outer edge ofthe wall surface part 11 a and that extends in an axial direction L, andan inner cylindrical part 11 c that is interposed between the wallsurface part 11 a and the cylindrical part 11 b and that is formedcoaxially with the cylindrical part 11 b inside the cylindrical part 11b.

The first sealing member 12 is molded out of rubber such as H-NBR, andhas an annular (cylindrical) base 12 a that is joined to a wall surfaceH1 of the housing H and that extends in the axial direction L, a firstlip part 12 b that extends almost conical inwardly in the radialdirection from the base 12 a and that defines a circular inner edge 12b′ coming into contact with the rotational shaft S, and an annular(cylindrical) concave part 12 c that has an opening 12 c′ at its endface (on the side of the air A) in the base 12 a and that is formed toreceive the cylindrical part 11 b, as shown in FIG. 3 and FIG. 4.

The first reinforcing member 11 is formed so that the wall surface part11 a can adjoin (can come into close contact with) a root area 12 b″ ofa first lip part 12 b in the axial direction L, whereby the first lippart 12 b is prevented from being deformed inwardly in the radialdirection beyond the allowable limits. Further, the first reinforcingmember 11 is formed so that the inner cylindrical part 11 c can befitted into the inside of the base 12 a, and a part 12 a″ of the base 12a (i.e., a part defined by the concave part 12 c and the innercircumferential surface of the base 12 a) can be supported radially in asandwiched manner in cooperation with the cylindrical part 11 b. As aresult, the first reinforcing member 11 and the first sealing member 12are reliably attached to each other.

The first sealing member 12 is provided with two projection parts 12 a′that annularly protrude outwardly in the radial direction on the outerperipheral surface of the base 12 a, whereby the adhesion with the wallsurface H1 is improved.

Next, a description will be given of assembling and disassembling of thelip-type seal 10. First, in assembling, the first reinforcing member 11and the first sealing member 12 are arranged in the axial direction L asshown in FIG. 3, and the cylindrical part 11 b of the first reinforcingmember 11 is fitted into the annular concave part 12 c formed on thebase 12 a of the first sealing member 12. Attaching is completed withease merely by fitting the cylindrical part 11 b into the annularconcave part 12 c without a caulking process or an adhesive. In thisstate, the base 12 a is reliably sandwiched between the cylindrical part11 b and the inner cylindrical part 11 c, so that these components arereliably attached to each other.

On the other hand, in disassembling, the first reinforcing member 11 andthe first sealing member 12 can be reliably separated merely by pullingout the cylindrical part 11 b from the annular concave part 12 c.Herein, since the first reinforcing member 11 has the wall surface part11 a exposed and integrally formed with the cylindrical part 11 b thatis fitted and buried in the concave part 12 c of the first sealingmember 12, the components can be easily disassembled by gripping thewall surface part 11 a, for example, while putting a finger into thecircular hole 11 a′ or while using a tool.

Further, when the lip-type seal 10 is attached to the compressor C, therotational shaft S is passed so that the inner edge 12 b′ of the firstlip part 12 b comes into contact with the outer peripheral surface ofthe rotational shaft S as shown in FIG. 4, the base 12 a of the firstsealing member 12 is then fitted to the wall surface H1, and a snap ringR is attached so as to come into contact with the first sealing member12 in a state in which the end face of the first reinforcing member 11is in contact with a wall surface H2.

The snap ring R has an inclined surface with an inclination angle θ ofabout 10 to 20 degrees, preferably 15 degrees, and presses the lip-typeseal 10 against the wall surface H2 by being fitted into an annulargroove H3 formed to likewise have an inclined surface in the housing H.

In this embodiment, the inner cylindrical part 11 c is provided in thefirst reinforcing member 11. However, without being limited to this, thepresent invention may have a structure in which the cylindrical part 11b is directly provided to be bent from the outer edge of the wallsurface part 11 a, without providing the inner cylindrical part 11 c.

FIG. 5 and FIG. 6 show another embodiment of the lip-type seal accordingto the present invention, in which a second sealing member and a secondreinforcing member are added to the components used in the foregoingembodiment. The same reference symbol is given to the same constituentelement as in the foregoing embodiment, and overlapping descriptionthereof is omitted.

As shown in FIG. 5 and FIG. 6, the lip-type seal 20 is made up of afirst reinforcing member 21 formed annularly, a first sealing member 22formed annularly, a second sealing member 23 sandwiched between thefirst reinforcing member 21 and the first sealing member 22, and asecond reinforcing member 24 fitted to the first sealing member 22 onthe side opposite the first reinforcing member 21.

The first reinforcing member 21 is formed by subjecting a metallicplate, such as a cold-rolled steel strip or a stainless steel plate, topress working, and, as shown in FIG. 5 and FIG. 6, has a wall surfacepart 21 a that defines a circular hole 21 a′ through which a rotationalshaft S is passed, a cylindrical part 21 b that is bent from the outeredge of the wall surface part 21 a and that extends in the axialdirection L, and a collar part 21 c formed by widening its radius in thebent region between the wall surface part 21 a and the cylindrical part21 b.

The wall surface part 21 a is provided with a plurality of projections21 a″ that serve as rotation stoppers arranged in the circumferentialdirection on the surface to which the second sealing member 23 isjoined. The projections 21 a″ can effectively restrict the rotation ofthe second sealing member 23 although the second sealing member 23 ismerely supported in a sandwiched manner.

The first sealing member 22 is molded out of rubber such as H-NBR, and,as shown in FIG. 5 and FIG. 6, has an annular (cylindrical) base 22 athat is joined to a wall surface H1 of the housing H and that extends inthe axial direction L, a first lip part 22 b that extends almost conicalinwardly in the radial direction from the base 22 a and that defines acircular inner edge 22 b′ coming into contact with the rotational shaftS, and an annular (cylindrical) concave part 22 c that has an opening 22c′ at its end face (on the side of the air A) in the base 22 a and thatis formed to receive the cylindrical part 21 b.

Two projection parts 22 a′ that annularly protrude outwardly in theradial direction are formed on the outer peripheral surface of the base22 a, whereby the adhesion with the wall surface H1 is improved as inthe foregoing embodiment.

The second sealing member 23 is molded out of resin such astetrafluoroethylene resin, and, as shown in FIG. 5 and FIG. 6, has ato-be-sandwiched part 23 a flatly formed with a circular outline so asto be sandwiched between the wall surface part 21 a and the root area 22b″ of the first lip part 22 b and a second lip part 23 b that extendsalmost conical inwardly in the radial direction from theto-be-sandwiched part 23 a and that defines a circular inner edge 23 b′coming into contact with the rotational shaft S.

Like the first reinforcing member 21, the second reinforcing member 24is formed by subjecting a metallic plate, such as a cold-rolled steelstrip or a stainless steel plate, to press working, and, as shown inFIG. 5 and FIG. 6, has a flat annular wall surface part 24 a that isbrought into contact with the end face (on the side of the internalspace B) of the base 22 a in the axial direction L, a cylindrical part24 b that is bent from the outer edge of the annular wall surface part24 a and that extends in the axial direction L, and a contact part 24 b′that is vertically bent at the end of the cylindrical part 24 b and thatcomes into contact with the root area 22 b″ of the first lip part 22 b.

Next, a description will be given of assembling and disassembling of thelip-type seal 20. First, in assembling, the first reinforcing member 21,the second sealing member 23, the first sealing member 22, and thesecond reinforcing member 24 are arranged in the axial direction L asshown in FIG. 5, the cylindrical part 21 b of the first reinforcingmember 21 is then fitted into the concave part 22 a of the first sealingmember 22 in such a way as to sandwich the to-be-sandwiched part 23 a ofthe second sealing member 23 therebetween, and the cylindrical part 24 bof the second reinforcing member 24 is fitted into the inside of thebase 22 a. The first reinforcing member 21, the first sealing member 22,the second sealing member 23, and the second reinforcing member 24 arecompletely assembled merely by fitting these components thereintowithout a caulking process or an adhesive.

In this state, the contact part 24 b′ of the second reinforcing member24 reliably supports the second sealing member 23 (the to-be-sandwichedpart 23 a) in a sandwiched manner in cooperation with the wall surfacepart 21 a of the first reinforcing member 21 while restricting thedeformation of the root area 22 b″ of the first lip part 22 b. Further,the projections 21 a″ of the wall surface part 21 a restricts therotation of the second sealing member 23 (to-be-sandwiched part 23 a),whereby the second sealing member 23 is reliably assembled to apredetermined position.

A part 22 a″ of the base 22 a (i.e., a part defined by the concave part22 c and the inner circumferential surface of the base 22 a) is reliablysandwiched in the radial direction between the cylindrical part 21 b ofthe first reinforcing member 21 and the cylindrical part 24 b of thesecond reinforcing member 24, so that the first reinforcing member 21,the first sealing member 22, and the second reinforcing member 24 arereliably assembled to each other.

On the other hand, in disassembling, the components can be reliablyseparated from each other merely by pulling out the cylindrical part 21b of the first reinforcing member 21 from the concave part 22 c and bypulling out the cylindrical part 24 b of the second reinforcing member24 from the inside of the base 22 a. As in the foregoing embodiment,since the first reinforcing member 21 has the wall surface part 21 aexposed and integrally formed with the cylindrical part 21 b that isfitted and buried in the concave part 22 c, the components can be easilydisassembled by gripping the wall surface part 21 a, for example, whileputting a finger into the circular hole 21 a′ or using a tool.

When the lip-type seal 20 is attached to the compressor C, a snap ring Ris attached as shown in FIG. 6 in the same way as in the foregoingembodiment.

Another method may be carried out as follows. Instead of the snap ringR, another member H′ disposed in the housing H (or, alternatively, apart of the housing H) is brought into contact with the annular wallsurface part 24 a of the second reinforcing member 24 from the axialdirection L, and the lip-type seal 20 is pressed against the wallsurface H2 as shown in FIG. 7.

In this embodiment, the projection 21 a″ is provided on the wall surfacepart 21 a as a rotation stopper that restricts the rotation of thesecond sealing member 23. Instead, a similar projection may be moldedintegrally with the root area 22 b″ of the first sealing member 22.

In this embodiment, the contact part 24 b′ is provided in the secondreinforcing member 24. However, the cylindrical part 24 b may beshortened, and the contact part 24 b′ may be removed as long as thesecond sealing member 23 is reliably sandwiched. Alternatively, thecylindrical part 24 b may be fitted to the inside of the base 22 a in aslightly loosened state.

FIG. 8 and FIG. 9 show still another embodiment of the lip-type sealaccording to the present invention, in which the second reinforcingmember shown in the above embodiment of FIG. 5 and FIG. 6 is changed.Therefore, the same reference symbol is given to the same structure asin the foregoing embodiment, and overlapping description thereof isomitted.

In this lip-type seal 20′, the second reinforcing member 24′ has arestriction part 24 c formed cylindrically so as to be bent furtherinwardly from the contact part 24 b′ and to extend in the axialdirection L, in addition to the annular wall surface part 24 a, thecylindrical part 24 b, and the contact part 24 b′, as shown in FIG. 8and FIG. 9.

As shown in FIG. 9, the restriction part 24 c is formed cylindrically soas to surround the first lip part 22 b outside in the radial directionof the first lip part 22 b in the assembled state, whereby the first lippart 22 b is prevented from being deformed outwardly beyond theallowable limits. Therefore, a desired sealing capability can be securedwithout influence of fluids in the internal space B.

As in the foregoing embodiment, in this lip-type seal 20′, thecomponents can be easily assembled and disassembled while securing sucha desired sealing capability.

FIG. 10 and FIG. 11 show still another embodiment of the lip-type sealaccording to the present invention, in which the first sealing membershown in the embodiment of FIG. 5 and FIG. 6 is partially changed and inwhich an annular spring 25 is added. Therefore, the same referencesymbol is given to the same structure as in the foregoing embodiment,and overlapping description thereof is omitted.

As shown in FIG. 10 and FIG. 11, in this lip-type seal 20″, the firstsealing member 22′ has an annular groove 22 b′″ formed in the outerperipheral surface of the first lip part 22 b, in addition to theannular base 22 a, the first lip part 22 b, the annular concave part 22c, and the opening 22 c′.

As shown in FIG. 10 and FIG. 11, the annular spring 25 is detachablyattached to the groove 22 b′″. The spring 25 always exerts apredetermined urging force onto the first lip part 22 b inwardly in theradial direction, and prevents the first lip part 22 b from beingdeformed outwardly beyond the allowable limits. Therefore, a desiredsealing capability can be secured without influence, for example, offluids in the internal space B. As in the foregoing embodiment, in thislip-type seal 20″, the components can be easily assembled anddisassembled while securing such a desired sealing capability.

FIG. 12 and FIG. 13 show still another embodiment of the lip-type sealaccording to the present invention, in which a third reinforcing member26 is added to the components shown in the embodiment of FIG. 5 and FIG.6. Therefore, the same reference symbol is given to the same structureas in the foregoing embodiment, and overlapping description thereof isomitted.

As shown in FIG. 12 and FIG. 13, in this lip-type seal 20′″, the thirdannular reinforcing member 26 is sandwiched between the first sealingmember 22 and the second sealing member 23.

The third reinforcing member 26 is formed by subjecting a metallicplate, such as a cold-rolled steel strip or a stainless steel plate, topress working, and, as shown in FIG. 12 and FIG. 13, has a substantiallyflat to-be-sandwiched part 26 a having a circular outline so as to besandwiched between the to-be-sandwiched part 23 a of the second sealingmember 23 and the root area 22 b″ of the first sealing member 22 and aslant surface part 26 b that extends almost conical inwardly in theradial direction from the to-be-sandwiched part 26 a and that defines acircular hole 26 b′ through which the rotational shaft S is passed.

As shown in FIG. 13, the slant surface part 26 b is formed to adjoin(come into close contact with) the first lip part 22 b of the firstsealing member 22, whereby the first lip part 22 b is prevented frombeing deformed inwardly beyond the allowable limits. Therefore, adesired sealing capability can be secured without influence, forexample, of fluids in the internal space B. As in the foregoingembodiment, in this lip-type seal 20′″, the components can be easilyassembled and disassembled while securing such a desired sealingcapability.

In the embodiments described above, the lip-type seals 10, 20, 20′, 20″,and 20′″ are applied to the compressor C that serves as apart of an airconditioning system, for example, of a vehicle. However, without beinglimited to this, the lip-type seal can be applied to any apparatus orelectrical appliance if these devices include a rotational shaft and ahousing which supports the rotational shaft.

INDUSTRIAL APPLICABILITY

As described above, the lip-type seal of the present invention is easilyattached, detached, and sorted while maintaining its desired sealingcapability, and hence a recycling process can be easily carried out.Therefore, the lip-type seal is useful in an apparatus or electricalappliance that is required to seal the outer periphery of its rotationalshaft with such a lip-type seal.

1. A lip-type seal with which an outer periphery of a rotational shaftsupported by a predetermined housing is to be sealed, the lip-type sealcomprising: a first reinforcing member formed annularly, the firstreinforcing member including a wall surface part defining a hole throughwhich the rotational shaft is to be passed and a cylindrical part bentfrom an outer edge of the wall surface part; and a first sealing member,the first sealing member including an annular base to be joined to thehousing, a first lip part that extends almost conically inwardly in aradial direction from the base so as to come into contact with therotational shaft, and an annular concave part formed on the base so asto detachably fit the cylindrical part; wherein the first reinforcingmember has an inner cylindrical part that supports the base in asandwiched manner from the inside in cooperation with the cylindricalpart, and the wall surface part extends from the inner cylindrical part.2. The lip-type seal as set forth in claim 1, wherein the wall surfacepart is contiguous to a root area of the first lip part in an axialdirection of the rotational shaft.
 3. A lip-type seal with which anouter periphery of a rotational shaft supported by a predeterminedhousing is to be sealed, the lip-type seal comprising: a firstreinforcing member formed annularly, the first reinforcing memberincluding a wall surface part defining a hole through which therotational shaft is to be passed and a cylindrical part bent from anouter edge of the wall surface part; a first sealing member, the firstsealing member including an annular base to be joined to the housing, afirst lip part that extends almost conically inwardly in a radialdirection from the base so as to come into contact with the rotationalshaft, and an annular concave part formed on the base so as todetachably fit the cylindrical part; a second sealing member that issandwiched between the first reinforcing member and the first sealingmember; and a second reinforcing member that is formed annularly andthat is fitted to the first sealing member on a side opposite the firstreinforcing member; wherein the second sealing member includes ato-be-sandwiched part that is sandwiched between the wall surface partand the root area of the first lip part; and a second lip part thatextends almost conically from the to-be-sandwiched part inwardly in aradial direction so as to come into contact with the rotational shaft;and wherein the second reinforcing member includes an annular wallsurface part that is brought into contact with the base in the axialdirection of the rotational shaft, and a cylindrical part that is bentfrom the inner edge of the annular wall surface and that is fitted tothe inside of the base.
 4. The lip-type seal as set forth in claim 3,wherein the first sealing member is made of rubber, and the secondsealing member is made of resin.
 5. The lip-type seal as set forth inclaim 3, wherein the cylindrical part of the second reinforcing memberhas a contact part that comes into contact with the root area of thefirst lip part in the axial direction of the rotational shaft.
 6. Thelip-type seal as set forth in claim 3, wherein the wall surface part ofthe first reinforcing member is provided with a rotation stopper thatrestricts the rotation of the second sealing member.
 7. The lip-typeseal as set forth in claim 3, wherein the second reinforcing member hasa restriction part that is bent from the cylindrical part inwardly so asto be cylindrical and that restricts deformation of the first lip partcaused outwardly in the radial direction of the first lip part within apredetermined range.
 8. The lip-type seal as set forth in claim 3,wherein the first sealing member is detachably provided with an annularspring that exerts an urging force inwardly in the radial direction inan outer peripheral area of the first lip part.
 9. The lip-type seal asset forth in claim 3, wherein a third reinforcing member that is formedannularly and that restricts deformation of the first lip part causedinwardly in the radial direction of the first lip part within apredetermined range is sandwiched between the first sealing member andthe second sealing member.